Is my A/C cold enough

cmf21

Senior member
Oct 10, 1999
977
1
81
Can anyone tell me what the AC vent temperture should be on a 04 Tacoma. I just recently bought it and I live here in SW Arizona. Previous owners also lived in SE California and had the system checked about 2yrs prior. The truck only has 46000 miles on it but I don't think the AC feels cold enough. I know I live here in the deseret with tempertures reaching 110+ during the day, but I think it should be a little colder like down in the 40's. Even after driving 30 minutes it isn't really much better. Before I the bought the truck, the dealer said that they had checked and filled system and told me it was 54 at the vent and was fine.

I was thinking about taking it somewhere else to have it checked. 54 at the vent doesn't seem right to me.
 

herrjimbo

Senior member
Aug 21, 2001
830
11
81
look at it this way. if your house was 54 degrees, you'd be freezing. it's not a brand new vehicle, and no matter what you do, it probably won't get any colder. just money out the window trying to figure it out.
 

JSt0rm

Lifer
Sep 5, 2000
27,399
3,947
126
I live in southern cali and when the sun is pumping the vents just help but dont make it cold. volvo s60
 

Zenmervolt

Elite member
Oct 22, 2000
24,514
34
91
If the vent temp is 54 degree when the external temperature is 100 degrees then the system is perfectly fine. At 100 degrees ambient, a vent temperature anywhere between 52 and 60 degrees is considered "normal".

Remember that A/C depends on transferring heat, any heat removed from the cabin must be deposited outside the car (via the condenser). As temperatures outside climb, it becomes exponentially difficult to make that transfer and vent temps climb.

Anywhere from 60 to 90 degrees ambient temperature should see vent temps between 44 and 50 degrees (with vent temps rising as ambient temperatures rise). However once the temperature gets above the 90s, vent temperatures tend to climb. At 100 degrees ambient, vent temps should be between 52 and 60 degrees. At 110 degrees ambient, vent temps should be between 68 and 74 degrees.

Reference: http://www.clarks-garage.com/shop-manual/hvac-02.htm

ZV
 

Rubycon

Madame President
Aug 10, 2005
17,768
485
126
Normal temp is determined by the return temp going across the evaporator. When the air is first started it's going to be much higher because the suction pressure is higher. You can calculate this based on the superheat spec of your AC unit. You cannot get instantly cold air unless you are pulling air across the evaporator from another location that's already cooler like outside in the case it's fairly cool outside and the sun has warmed the cabin. In that case it would be easier to open the windows. :p
 

hanoverphist

Diamond Member
Dec 7, 2006
9,867
23
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in phx on a hot day like today id LOVE to have it be 54 at the vent. i have an older truck with a ton of miles on it, as well as an old compressor. it will still cool down inside if i dont crack the windows and i use the recirc option. face it, taking 110 degree air and trying to instacool it isnt very efficient, and sometimes not very effective.
 

Pacfanweb

Lifer
Jan 2, 2000
13,155
59
91
54 should feel freezing at those outside temps. That's a pretty good number. Some cars might do better, but that's still a very acceptable number.
 

cmf21

Senior member
Oct 10, 1999
977
1
81
Drove around today for a good hour but it still didn't feel very cold. Just cool. I don't know if the dealer was just telling it was ok so I would leave them alone. I'm probably just going to take it somewhere and have it checked becasue my other cars seem to cool down alot faster and feel colder.
 

brblx

Diamond Member
Mar 23, 2009
5,499
2
0
54 is certainly not cold. it routinely stays 90-100* here in the summer, and i can tell you that people are not happy with a >50* vent temp. even in the dead of summer, i can get a car with good AC into the 30's. heck, i've had volvo 240's down to 45 or better on a 90*+ day, and the AC in those cars is AWFUL. you also have to consider how low the humidity typically is in arizona.

do you know how the shop measured? if it's >50 with the windows up and recirc on, i'd say the charge may be a little low.

 

Pacfanweb

Lifer
Jan 2, 2000
13,155
59
91
Originally posted by: cmf21
Drove around today for a good hour but it still didn't feel very cold. Just cool. I don't know if the dealer was just telling it was ok so I would leave them alone. I'm probably just going to take it somewhere and have it checked becasue my other cars seem to cool down alot faster and feel colder.
You are using the recirculation or max setting, aren't you? If not, you'll never get it very cold.

54 is within specs, but upon further review, I will admit that most of my vehicles cool better than that, regardless of how hot it gets.

But it gets in the mid-upper 90's here, with the occasional 1-oh, but with more humidity than the desert.

But the A/C doesn't care about humidity, that ambient temp of 110 might just be killing it.

Maybe you could find a similar vehicle on their lot and ask them to compare it.
 

cmf21

Senior member
Oct 10, 1999
977
1
81
Well I checked what service they did when they got the truck. Looks like it says it had a low system charge and blowing warm. They added dye and freon. When I took it back, they checked it again and said the ac operating as designed with 54 degrees @ cruise.

I don't believe they checked the system the second time and will be taking it somewhere else in the next few days. Some other people on another forum who own the same truck says it should be much lower.
 

npoe1

Senior member
Jul 28, 2005
592
0
76
I think your temperatures are fine; For curiosity what were your previous car temps?
 

Zenmervolt

Elite member
Oct 22, 2000
24,514
34
91
Originally posted by: brblx
54 is certainly not cold. it routinely stays 90-100* here in the summer, and i can tell you that people are not happy with a >50* vent temp. even in the dead of summer, i can get a car with good AC into the 30's. heck, i've had volvo 240's down to 45 or better on a 90*+ day, and the AC in those cars is AWFUL. you also have to consider how low the humidity typically is in arizona.

do you know how the shop measured? if it's >50 with the windows up and recirc on, i'd say the charge may be a little low.

As pointed out earlier, vent temps rise exponentially as the ambient temperature rises. You absolutely cannot compare vent temps at 90 degrees to vent temps at 110 degrees. It flat isn't valid.

At 100 degrees ambient, a 54 degree vent temp is within spec. At 110 degrees, a 54 degree vent temp is fantastic. At 90 degrees, it's unacceptable. It all depends on the ambient temperature.

ZV
 

Pacfanweb

Lifer
Jan 2, 2000
13,155
59
91
I'm going to try to remember to check the temp on my Suburban tomorrow. In the upper-90's we get here, it will flat run you out of there if you leave it on max with the temp on the coldest setting.
 

JulesMaximus

No Lifer
Jul 3, 2003
74,544
924
126
Originally posted by: Pacfanweb
54 should feel freezing at those outside temps. That's a pretty good number. Some cars might do better, but that's still a very acceptable number.

Agreed. I was in Palm Springs over the weekend and on Sunday the temps hit 117 outside. I had the A/C in the house we were staying in at 78 degrees and it felt freezing in there.
 

cmf21

Senior member
Oct 10, 1999
977
1
81
I took it in today and found that it was charged a little more then half. Dealer must have been lying to me that they filled it or there is a leak that can't be found. I ended up having it filled and it now and it seems much better. It's 115 outside but every little bit helps.
 

brblx

Diamond Member
Mar 23, 2009
5,499
2
0
did they go over it with a UV light? for the charge to be low, there's gotta be a leak somewhere. heck, my primary car still has the original charge from 1999, and has only recently started to become a little warm (i still probably won't top it off and dye it until next summer).

Originally posted by: Zenmervolt
Originally posted by: brblx
54 is certainly not cold. it routinely stays 90-100* here in the summer, and i can tell you that people are not happy with a >50* vent temp. even in the dead of summer, i can get a car with good AC into the 30's. heck, i've had volvo 240's down to 45 or better on a 90*+ day, and the AC in those cars is AWFUL. you also have to consider how low the humidity typically is in arizona.

do you know how the shop measured? if it's >50 with the windows up and recirc on, i'd say the charge may be a little low.

As pointed out earlier, vent temps rise exponentially as the ambient temperature rises. You absolutely cannot compare vent temps at 90 degrees to vent temps at 110 degrees. It flat isn't valid.

At 100 degrees ambient, a 54 degree vent temp is within spec. At 110 degrees, a 54 degree vent temp is fantastic. At 90 degrees, it's unacceptable. It all depends on the ambient temperature.

ZV

OP would care to disagree, apparently.

i don't know if you've worked on cars professionally or not, but i can tell you that if you let customers' vehicles go with a 54* vent temp, SOMEONE is going to working on that car again. yeah, if i go pull a book out, i'm sure i can find a chart that says 50-60* is 'normal' for an 100* day, but i can tell you flat out that i've stood in a 100* shop, measured vent temps in the 50-60* range, and fixed them. 54*, even when it's a 100 out, doesn't feel cold; probably because the air has dispersed and warmed significantly by the time it even gets to you (keeping in mind temps are usually measured ~6" down into the vent because of the design of most tech's thermometers).

when i first started working on cars, i got laughed at for using words like 'theoretically,' and for good reason.
 

shawn roddick

Junior Member
Aug 18, 2017
1
0
1
i know this is an old topic but i have to say i find it a bit rediculous how many people are saying 54 is fine that is 14 degrees higher that what it should be lol! the average a/c in a car nn matter if its 120 outside should be within a 40 degree range if properly charge....i have a 2008 cobalt ss and i have played with my a/c when it was 117 outside. when i drive it around it gets down to around 42 at the vents when 105 outside i am getting between 39 and 41 at the vents when 85 to 90 i get 36 to 37 at the vents every little bit helps but you have to check your temps and if they are in the 50s your not cooling properly i live in las vegas nv.
 

razel

Platinum Member
May 14, 2002
2,337
93
101
I took it in today and found that it was charged a little more then half. Dealer must have been lying to me that they filled it or there is a leak that can't be found. I ended up having it filled and it now and it seems much better.

Now that you know, you can keep watch on it. If you frequently have to refill, then there is a leak. Don't get comfortable refilling it as a permanent fix. It'll cost you more to repair it correctly later than plugging the leak now. So I suppose it depends how long you plan on keeping the car. Again, that all assumes you have a leak.
 
Feb 25, 2011
16,980
1,616
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So for people in hot climates, are aftermarket condensers a thing?

I live in Minnesota, so this doesn't apply to me, but I'm curious.
 

chin311

Diamond Member
Feb 27, 2003
4,306
3
81
Speaking of A/C, my Altima has been doing weird things. Sometimes when I first get in it for the day, it will not get cool/cold air coming out of the vents until I get driving OR if I raise the RPMs to 2-2500 for 10-20 seconds. Then it might be fine for the day or multiple days before it spazzes out again. Also sometimes it feels a whole lot colder than other times. It's only got 44000 miles on it too. Gonna have the dealer look @ it after reading a lot of horror stories online seems it might be $1000 or more :(
 
Feb 25, 2011
16,980
1,616
126
Speaking of A/C, my Altima has been doing weird things. Sometimes when I first get in it for the day, it will not get cool/cold air coming out of the vents until I get driving OR if I raise the RPMs to 2-2500 for 10-20 seconds. Then it might be fine for the day or multiple days before it spazzes out again. Also sometimes it feels a whole lot colder than other times. It's only got 44000 miles on it too. Gonna have the dealer look @ it after reading a lot of horror stories online seems it might be $1000 or more :(
I had issues like that with my old Focus. A/C would cut in / cut out depending on engine temps and whatnot.

Refrigerant was low. Probably a very slow leak somewhere, but a shop recharged it and it was fine for another couple years before I got rid of it.
 

bruceb

Diamond Member
Aug 20, 2004
8,874
111
106
Generally on R134A systems, the low side pressure will be in the mid to high 40 Lb range (towards the higher side the hotter the ambient temperature is) .. And also the higher the temperature and humidity, the less the AC can take down the temperature. Expect to see about 45 deg or so at the vents on just a hot day, with little humidity (say about 30%)